Bowker was on his hands and knees in the door of the store, bleeding so heavily that investigators initially couldn't see his wounds. He said he'd been robbed and beaten before it appeared he was losing consciousness.

"From the outward appearances, it looks like they were trying to kill him," Sheriff's Sgt. Mike Dougherty said.

Dougherty said Bowker is an independent cab driver who takes people home who are too intoxicated to drive. Investigators heard he charged a $5 flat rate.

"He's a very well-known taxi cab driver to the bars, pretty much to the nightlife scene," Dougherty said. "He had a relationship with all the different bars and some of the bouncers at the different clubs."

Investigators found a trail of blood from Bowker's vehicle, a silver 2000 Ford, to the area where he collapsed. The vehicle was in the parking lot in front of the store.

Dougherty said a possibility investigators are examining is that Bowker dropped a customer off, got attacked and drove to the nearest place open. Dougherty said investigators have identified the scene where Bowker is thought to have been injured.

"There's no reason to believe anything else other than it would have been a customer," Dougherty said.

He said from the amount and rate of blood loss, it didn't appear Bowker could have gotten far.

"He had multiple stab wounds to his head ... and neck and face and he also had a lot of trauma to his cheek where it broke his orbital eye socket along with crushed part of his skull," Dougherty said.

He said investigators determined he'd picked several people up earlier and taken them to various locations.

"We're following up on several different leads right now," Dougherty said. "We're following up, eliminating people, speaking with some people further."